SCATTERED THUNDERSTORMS WILL CONTINUE TO DEVELOP ACROSS MUCH OF
SOUTHWEST LOWER MICHIGAN THROUGH 2 PM. THE STRONGER STORMS WILL BE
ACCOMPANIED SMALL HAIL…WIND GUSTS OVER 50 MPH…HEAVY RAIN AND
FREQUENT LIGHTNING.

THE CHANCES FOR SEVERE THUNDERSTORMS WILL INCREASE…ESPECIALLY
AFTER 2 PM THIS AFTERNOON. THE GREATEST THREATS WILL BE DAMAGING
WINDS AND LOCALLY HEAVY RAINFALL.

IF SKIES DARKEN IN YOUR AREA CURTAIL ANY OUTDOOR ACTIVITIES AND
SEEK SHELTER UNTIL 30 MINUTES AFTER THE STORM HAS PASSED. IF
CAUGHT OUTSIDE STAY AWAY FROM HIGH OBJECTS SUCH AS TREES.

A LEAD SHORTWAVE TROUGH OVER NW WI/WRN UPPER MI WILL PROGRESS EWD
OVER NRN LOWER MI TODAY…AS THE PRIMARY UPSTREAM TROUGH OVER NE
MANITOBA DIGS SEWD OVER ONTARIO. ASSOCIATED CYCLOGENESIS ACROSS
QUEBEC /JUST E OF JAMES BAY/ WILL HELP DRIVE A COLD FRONT SEWD
ACROSS THE CENTRAL PLAINS…UPPER MS VALLEY…AND UPPER GREAT LAKES
BY TONIGHT.

A BROKEN BAND OF CONVECTION HAS CROSSED NRN LOWER MI AS OF MID
MORNING IN ADVANCE OF THE LEAD SHORTWAVE TROUGH…WHILE A SECOND
BAND IS ONGOING OVER WRN UPPER MI AND FAR NRN WI ALONG THE SURFACE
COLD FRONT. THE STRONGEST SURFACE HEATING AND GREATEST
DESTABILIZATION WILL OCCUR TODAY ALONG AND SE OF THE PRE-FRONTAL
CONVECTIVE BAND FROM NRN IL TO LOWER MI…WHERE AFTERNOON SURFACE
TEMPERATURES IN THE UPPER 80 TO LOWER 90S WILL REMOVE CONVECTIVE
INHIBITION AND CONTRIBUTE TO MLCAPE OF 1500-2500 J/KG.
UNIDIRECTIONAL WIND PROFILES WITH 35-45 KT MEAN WLY LOW-MIDLEVEL
FLOW WILL COMBINE WITH THE MODERATE BUOYANCY AND STEEPENING
LOW-LEVEL LAPSE RATES TO RESULT IN A RISK FOR DAMAGING WINDS WITH
THE STRONGER EMBEDDED STORMS/LINE SEGMENTS.

THERE ARE SOME CONCERNS REGARDING THE MAGNITUDE AND COVERAGE OF THE
DAMAGING WIND RISK THIS AFTERNOON. LOW-LEVEL CONVERGENCE IS WEAK AT
BEST WITHIN THE PRE-FRONTAL BAND FROM NRN IL TO LOWER MI WHICH
BRINGS INTO QUESTION THE ORGANIZATION AND COVERAGE OF STORMS.
ALSO…THE STRONGEST LOW-MIDLEVEL FLOW AND POTENTIAL FOR MOMENTUM
TRANSFER WILL RESIDE FARTHER N ACROSS NRN LOWER MI WHERE STORMS THIS
MORNING HAVE INTERRUPTED THE DIURNAL CYCLE OF DESTABILIZATION. THE
NET RESULT IS SOMEWHAT QUESTIONABLE PHASING OF THE STRONGER FLOW
FIELDS AND LARGER-SCALE ASCENT WITH THE MORE UNSTABLE WARM SECTOR.
STILL…WILL MAINTAIN THE RISK FOR A FEW DAMAGING GUSTS GIVEN THE
ONGOING STORMS IN LOWER MI…AND SOME POTENTIAL FOR INTENSIFICATION
LATER THIS AFTERNOON OF THE CONVECTION ALONG THE COLD FRONT.

I realize that, but where was the lake shadow 15 or 20 years ago when we used to watch storm after storm roll in over the lake and plow right through this area? The past 10 years it’s like something has changed and everything just skips over us. Oh well, lots less gas I have to buy for the mowers. I’ve only mowed once since we got back from vacation in mid-June.

I’m sure there were plenty of lake shadow days 15-20 years ago too. We’ve also been nailed plenty of times in the last 10 years by storms crossing or even developing over the lake. In the absence of actual numbers, I think we can just assume the boom:hype ratio has remained fairly consistent over the decades. Memory biases, after all, they really make it tough to judge past experiences.

I knew I didn’t quite feel it happening. I was cautious on this system, this far out being called by SPC usually does end up as a downer. Well than, I’d like to say there is 2014, but that to will probably be like any other year over the last few years, getting shafted and skipped over. Boy the farmers sure need a break it’s either late frost/freeze that kills the crops or a drought. *SIGH* Just threw in the towel. Back to our regular program.

We shall see, maybe for your neck of the woods but I’ll be the spectator AGAIN. I just feel we’ll just get skimmed but we shall see, I’m going to hold you to your ETA, you’ve been keeping that time set in stone with me so I’m holding you to it.

The HRRR also agrees that the main event will be this evening along the cold front. Click here, and keep in mind to not focus on the specific storm cells, but just look at the general picture. Also, the HRRR has had a tendency to overdo thunderstorm coverage lately.

Current Michigan radar mosaic: Click here. The storms up north are being triggered by the cold front.

Looks like the Gaylord, Detroit, and Grand Rapids NWS offices and the SPC wanted to cover both the severe storms up by Mackinac and the severe storms over by Saginaw with one watch. The Grand Rapids and Detroit offices have the option of expanding the watch southward if the mid-Michigan storms do become more widespread and severe farther south.

DISCUSSION…BROKEN BANDS OF CONVECTION ARE FORMING ALONG THE SURFACE COLD FRONT APPROACHING NW LOWER MI…AND ALONG A DIFFUSE PRE-FRONTAL TROUGH ACROSS CENTRAL LOWER MI. CONTINUED DESTABILIZATION AND 35-50 KT WLY WIND PROFILES WILL SUPPORT A RISK OF DAMAGING WINDS AND ISOLATED LARGE HAIL WITH THE STRONGER CELL/LINE SEGMENTS THROUGH THE AFTERNOON/EVENING.

Good keen observation. According to the watch box itself — Allegan, Barry, Eaton and Ingham were added, but barely touched by the watch box. I think, however, a separate watch would be needed south, because in GRR’s interest, they only have one set of counties to go and the box would likely be needed further south.

Probabilities of the watch — I’ve seen better. Only a 30% chance of 10 wind reports and 60% of 6 or more events in the watch box. Definitely have seen better watch probabilities.

Before anyone gets too excited about the “d” word… The unidirectional wind shear is good for organized lines with straight-line microburst winds, but the orientation of the triggers (cold front and pre-frontal trough) roughly parallel to the wind shear will not create the classic progressive derecho scenario that we are all familiar with.

Plus, if I’m not mistaken and these parameters were in fact correct with the shear and instability, it would be very close, if not exceeding some parameters of the June 12 derecho. Someone correct me if I’m wrong.

The last Grand Rapids derecho… 2 years ago with this monster! (a href=http://mesonet.agron.iastate.edu/current/mcview.phtml?prod=lotrad&java=script&mode=archive&frames=45&interval=10&year=2011&month=7&day=11&hour=5&minute=0>Click here)

Northern Indiana-Ohio had a derecho last month, and also last year in June. Summertime derechos are more common in that corridor, and every 2-3 years or so one will blast through West Michigan.

We had the northern end here in Van Buren County with that derecho. Likely over 70+ mph winds, because the GLERL site at South Haven reported 74 mph winds. It wasn’t really a typical derecho-type storm. Typically, the leading edge in advance is where we get the winds. It was rain with little wind to start then…BOOM went the dynamite.

Heard on Ham radio that many powerlines poles snapped 5 miles east of Mt. Pleasant with Coleman Rd north of m-20 closed due many tree limbs, powerlines, telephones down. Can’t get through due to power outage.

Depends who you talk to. For storm buffs, to have a Day 6, Day 5 and Day 4 30% or greater probabilities and Day 3, Day 2 and Day 1 Slight Risk, they may be disappointed. To those who don’t like storms, some will be overjoyed. I would like no severe storms, but some rain would be nice.

It will as I don’t really expect to see much but we’ll see I’m going fishing here within the hour with my son and we’ll see how well they are biting. Will bring my camera and get ready to take photos if anything decides to move on in and I can drive up to Fisk Knob to watch them come in.

Man the weather really has sucked!!! I think I am going to move to the plains where they get storms all the time, well almost, all the time!! These 5 minutes showers with tiny thunder are really starting to suck!! If I wanted weather like this to continue I would live in Seattle!! Where it rains like crazy a lot but not a lot of boomers. Feeling depressed.